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Article History

Received: 29 January 2018

Accepted: 29 June 2018

First Online: 5 July 2018

Ethics approval and consent to participate

: All procedures performed in studies involving human participants were conducted in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Institutional review board approval was obtained from Nihon University Itabashi Hospital (approval number RK-11209-8).

: Not applicable

: The authors declare that they have no competing interests.

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